"The scrutiny that that you come under when you are making a movie that based on real events is sometimes overwhelming," says Oscar winner William Goldenberg.

Discussing his work on the headline-making Concussion, editor William Goldenberg — a five-time Academy Award nominee who won an Oscar for Argo — admits that"the scrutiny that you come under when you are making a movie that's based on a real event is sometimes overwhelming."

Columbia's Concussion tells the story of Dr. Bennet Omalu, played by Will Smith, whose study of chronic traumatic encephalopathy (CTE) was met with fierce resistance by the NFL. Peter Landesman directed and wrote the screenplay, based on a GQ article and then a book by Jeanne Marie Laskas.

Goldenberg, whose next project is Ben Affleck’s Live by Night, talked with The Hollywood Reporter about the challenges of editing Concussion as well as the film's touchy subject matter.

I would imagine discussions about the editing involved how much artistic license to use and to what extent the NFL is vilified? Is that fair to say and how did you address it?

It is fair to say. We wanted to make this more pro-player and not anti-NFL. We wanted to present the facts as they were. We wanted to be fair and accurate. Because of the potential for lawsuits or interference from the NFL, or them saying "it’s not true," we were very careful. We had lawyers in the room three times a week during postproduction, making sure what we were doing was accurate. At no time did we do anything that compromised the film, but we wanted o make sure it was accurate and as it happened. Peter used to be an investigative journalist and he did really extensive research while he was writing the screenplay. And while we were cutting we showed the film to Bennet and several neurologists who consulted during the writing, again to make sure the science was right. We showed the film to a couple ex-NFL players as well as to make sure we had the football right.

What was the most challenging scene to edit?

The scene when [Omalu] figures it out that this is a horrible disease that's being caused by the hits to the head. The spine of that sequence is a show that used to be on ESPN, where they would celebrate the top five hits of the week. Peter wrote the scene with that as the centerpiece [with Omalu watching]. It runs about 2 ½ to 3 minutes. It finished with him with an onion in a jar in water and him demonstrating to his girlfriend what happens to the brain. There was ton of footage, and giving that a dramatic structure was really difficult. We moved things around a lot. There were lot of sources: stock footage (which could be used due to fair use rights), what production had shot — plus we had the visual effects shot that snaps into [NFL player] Mike Webster's head and you see what happens to the human brain banging off the skull.

The pace was getting quicker in that scene; I felt his mind was racing.

Yes, that was the intention. All of this information [the videos of the hits, the X-rays, the information he’d been reading, etc.] cascades down on him and then the light bulb goes off.

Looking back on some of your work, specifically Concussion, The Insider and last year’s The Imitation Game, there’s a trend.

Yes, I’m attracted to movies that are about unsung heroes, and people struggling against a huge entity. I think part of what attracts me is a small story on a huge canvas: Alan Turing trying to win the war in a hut outside London (Imitation Game), Jeffrey Wigand going to battle with the cigarette industry (The Insider), or in this case, Bennet goes up to battle with what turns out to be the biggest American sport while he’s trying to fulfill his American dream. I’ll always try to make the audience feel as if they are going through it with that person, and make sure they see it through the eyes of our protagonist. [But] the scrutiny that you come under when you are making a movie that's based on a real event is sometimes overwhelming. We are always trying to stay true to the sprit of the event, but it’s also a dramatic film, not a documentary.

Concussion has certainly sparked discussion about brain injury. Among the coverage, it's been reported that an exec at the NFL Players Association is recommending it to members. What do hope people will take away from this?

Everyone is going to have their own opinion on this. The facts are the facts: With repetitive head blows, you have a much bigger chance of having a brain injury, CTE or some other conative disorder. I hope parents realize how dangerous concussions are, especially in young people. If the movie does that, even a little bit, that would be great. … It seems to have moved the conversation along. It seems like we’re seeing more information about concussions and the dangers of blows to the head. I hope it moves the needle a little bit. Certainly in the NFL but also in soccer, rugby, hockey and peewee football — to make the information available so that parents can make an informed decision. I guess that's all you can ask for. It's very complicated. I still watch football, but I watch it with one eye closed now. I feel guilty about watching it. And I know Peter won't watch it anymore.